Three randomized trials (SATURN, ATLAS and IFCT-GFPC 0502) have demonstrated that the oral antiepidermal growth factor receptor tyrosine kinase inhibitor erlotinib can improve progression-free survival (PFS) and overall survival (OS), as maintenance therapy after first-line chemotherapy in advanced non-small cell lung cancer. We pooled the results of these three trials by performing a meta-analysis of hazard ratios (HRs) and the 95% confidence intervals (CIs) for the PFS and the OS for maintenance erlotinib versus observation, standard therapy or placebo. The benefits in the predefined subgroups of patients [according to histology, sex, performance status (PS), and smoking status] were assessed. The OS was superior in the 963 patients treated with erlotinib than in the 979 nontreated patients [HR=0.87 (P=0.003), corresponding to a 13% reduction in the risk of death. The pooled HR for the PFS is 0.76 (P<0.00001), corresponding to a 24% lower risk of being progression free]. All the patients in the subgroup analysis experienced a benefit from erlotinib and, in particular, never-smoking women with nonsquamous histology with a PS of 0. Both responders and those with stable disease obtain PFS benefit. The addition of maintenance erlotinib significantly improves PFS and OS in patients with advanced non-small cell lung cancer who had not progressed after four cycles of first-line chemotherapy. The benefit does not seem to be limited to a particular subgroup, although it is more pronounced in never-smoking women patients with nonsquamous carriers with a PS of 0.